Storage box having a retention portion



FIG. 1 is a rear perpective view of a storage box having a retention portion, showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a left end view thereof;

FIG. 5 is a right end view thereof;

FIG. 6 is a right side view thereof; and,

FIG. 7 is a left side view thereof.

The broken lines showing is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a storage box having a retention portion, as shown and described. 